1. Field of the Invention
The present invention is directed to a denture apparatus for removable dentures. In particular, the present invention is directed to a denture apparatus for removable dentures which will provide a force to urge the lower denture away from the upper denture in order to assist in retaining the dentures in proper position during eating.
2. Prior Art
In various instances, prosthodontic dentistry calls for the replacement of teeth with dentures. This may be called for in various instances including periodontal disease, decay or injury. Although it may be possible to surgically connect dentures to the jaw, removable dentures are often prescribed.
Where a full denture is utilized, the base of the upper denture normally covers the palate. The lower denture may be horseshoe-shaped to leave room for the tongue. A full denture is supported by the underlying gum and bone tissues of the dental ridge.
A lower denture is less stable than an upper denture. Moreover, it is known that a full denture can stand only very limited chewing pressure. When a denture wearer is eating with the dentures in place, the lower plate has a tendency to be displaced or flip up when the wearer is biting in the front or on the sides.
At least one estimate is that full dentures can only withstand one-tenth the chewing pressure of natural teeth.
Various provisions have been made in the past to affix or connect the upper denture to the lower denture. Examples of such approaches in Liedberg (U.S. Pat. No. 2,252,935), Anderson (U.S. Pat. No. 1,761,902) and Elsas (U.S. Pat. No. 1,473,673).
Morris (U.S. Pat. No. 3,043,005) discloses a dental anchoring system having a pair of leaf springs affixed to one of the plates to exert an anchoring separation of the plates.
One of the Applicants herein, Barnes (U.S. Pat. No. 5,286,198), has provided a denture apparatus with coil springs, each having an extending leg to engage the lower denture. By not connecting the lower to the upper denture, lateral and longitudinal movement of the dentures with respect to each other is allowed.
It is desirable to provide a denture apparatus to provide a force to urge the lower denture away from the upper denture with a spring which is removable from the denture apparatus.
Accordingly, it is a principal object and purpose of the present invention to provide a denture apparatus which will provide a force to retain and stabilize the position of the dentures during eating.
It is an additional object and purpose of the present invention to provide a denture apparatus having springs and spring enclosure assemblies that will not promote abrading or pinching of the mouth tissue.
It is an additional object and purpose of the present invention to provide upper and lower dentures that have full lateral and longitudinal movement with respect to each other.